Hallucination sufferers who also have Alzheimer’s disease are five times more likely to be misdiagnosed with dementia with Lewy bodies compared to patients who do not. This new research, conducted by scientists at Memory Disorders Clinic at St. Michael’s Hospital in Toronto, found that Alzheimer’s disease was misdiagnosed in 24 percent of all cases, with false positive and false negative rates both being 12 per cent. Previous research suggested that the rate of misdiagnosis in Alzheimer’s disease ranged from 12-23 percent. Why is a correct diagnosis so important? The two conditions are different in important ways. Alzheimer’s disease, actually a type of dementia, is characterized by protein deposits in the brain and twisted fibers found inside brain cells. Dementia with Lewy bodies, on the other hand, is believed to be caused by the buildup of a different abnormal protein aggregate found in nerve cells in the brain. Although effective treatments for both conditions are continuously being developed as new research advances, the authors believe that effective treatments for the two very different forms of dementia will almost certainly be different. In addition, clinicians are more reluctant to diagnose a patient with Alzheimer’s disease when they present with delusions or hallucinations because other types of dementia, like Parkinson’s disease and dementia with Lewy bodies have psychosis as a defining characteristic.